Electric vehicles are vehicles that use one or more electric engines for propulsion of the vehicle. The electric engines are powered by rechargeable batteries on-board the vehicle. Because electric vehicles are powered by on-board batteries, their driving range is limited by the amount of charge in their batteries. When a vehicle's batteries get low on charge, the vehicle can be recharged at a charging station. However, currently there is a limited number of charging stations for electric vehicles. Therefore, it is important for the driver to know the electric vehicle's current state of charge at all times even when the driver is away from the vehicle.
Being able to remotely access an electric vehicle's current state of charge is beneficial in that if the driver decides to travel to a destination, the driver remotely accesses the vehicle's state of charge and based on the accessed information determines whether the destination can be reached. If the vehicle does not have sufficient charge to reach the destination, the driver can alter his plans, for example, by allowing the vehicle to continue charging if it is connected to a charging station or by selecting a new destination that is within the vehicle's range.
Current systems allow a driver to remotely obtain an electric vehicle's current state of charge via a mobile device, such as a cell phone. The mobile device communicates with the vehicle to obtain the vehicle's state of charge. A problem with theses current systems is that if the mobile device is not able to communicate with the electric vehicle, the mobile device has no way of being able to determine the vehicle's current state of charge. A reason that the mobile device may not be able to communicate with the electric vehicle is because the vehicle is parked in a location where it is not able to access a wireless communication network. For example, the vehicle may be parked in an underground garage where there is no cell phone reception.
Thus, there is a need for a way to be able to remotely determine an electric vehicle's state of charge even when it is not possible to communicate with the electric vehicle.